Skin grafting device



C. P. VALLJS June 27, 198? SKIN GRAFTING DEVICE 2 Sheets-Sheet 1 FiledDec. 15 1963 INVENTOR CHARLES P. VALLIS W,W+M

ATTORNEYS June 27, 1967 c. P. VALLIS 3,327,711

SKIN GRAFTING DEVICE Filed Dec. 13, 1963 2 Sheets-Sheet :2

FIG. 4

INVENTOR. CHARLES P. VALLIS AT TORJN EYS United States Patent 3,327,711SKIN GRAFTING DEVICE Charles P. Vallis, 109 Lowell St., Lynnfield, Mass.01940 Filed Dec. 13, 1963, Ser. No. 330,421 8 Claims. (Cl. 128-305) Thisinvention relates in general to skin grafting and in particular to amanually operated precision dermatorne for cutting a uniform segment ofskin from the body surface.

Skin grafting is becoming an increasingly important operative procedurefor cosmetic and functional repair and for reconstruction of soft tissuedefects. Because the success of such procedures is dependent in largepart on the quality and uniformity of the segment of skin used in thegrafting, much thought has gone into the design of suitable instrumentsfor taking intermediate split skin grafts.

Fundamentally, all of the dermatomes that have been developed follow thegeneral principle of placing a sharp cutting edge in close apposition tothe skin surface. To accomplish the desired relationship between theblade and the skin, numerous techniques and devices have been proposedand used. In one Well known technique, a vacuum device is utilized toelevate the skin and to maintain it at the edge of the blade. In otherinstruments the skin is literally glued to a metal drum or to adisposable member of cloth, rubber or plastic by which the skin may beelevated to a proper position relative to the cutting blade. In someinstances the knife blade is reciprocated manually, and in otherinstruments an electric motor oscillates the cutting blade while theblade is held firmly against the skin.

Various refinements have been added to instruments of the type describedincluding one wherein rollers are mounted ahead of and behind theoscillating blade to distribute evenly the tension in the skin as it iscontacted by the cutting edge. Dermatomes such as those described havebeen reasonably successful, although much experience is usually requiredbefore the necessary degree of skill is ultimately developed by thesurgeon.

There are also certain inherent problems associated with the use of thevarious instruments described. In those instruments where glue is usedto raise the skin to the cutting position, the maintenance of consistentadhesive qualities in the glue is frequently difficult or impossible,preventing the necessary uniformity of cutting. Where a vacuum is usedto raise the skin to the cutting position, a compromise must be madebetween easy manipulation of the instrument and the maintenance ofsufficient vacuum to bring the skin to the desired cutting position. Inthose instruments which are electrically driven from a conventionalsource, the power cord impedes free movement and occasionally interfereswith other equipment or supplies, inhibiting proper operation. Moreover,although explosion-proof motors have been developed, even where powercords are eliminated, there is always some risk of explosion because ofthe highly volatile and inflammable nature of anesthetic agents whichare necessarily present during use of the skin grafting instrument.Also, of course, instrument sterilization is essential, and electricalequipment must be specially designed and protected to be so treated inan autoclave.

It is, therefore, a primary object of the present invention to improveand simplify the taking of skin grafts.

Another object of the present invention is to void the danger ofexplosion and the difiiculties of manipulation and sterilizationassociated with electrically driven instruments.

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A further object is to maintain not only predetermined uniform thicknessof skin segments being cut from the skin surface, but also predeterminedand uniform width of skin segments being cut from the skin surface.

A still further object is to standardize the taking of skin grafts bythe utilization of replaceable knife blades.

In general, the present invention consists in a cutting instrument inwhich metal rollers are mounted in relationship to a cutting blade suchthat the skin is brought to the blade as a uniform mound of tissueagainst which the blade may be manually reciprocated by the surgeon. Therollers serve the additional function of permitting free and balancedmovement of the instrument over the skirr surface. A micrometer headprovides precise vertical adjustment of blade guards to determine thedepth of the cut, and the same blade guards are adjustable horizontallyto vary precisely the width of skin being cut as the blade isreciprocated. The blade is retained in a holder which opens easily forquick change of blade, and the holder is also provided with a. positivelock to retain the blade in a fixed position during use of theinstrument. For a better understanding of the present invention,together with other and further objects, advantages and features,reference should be made to the following detailed specificationthereof, which should be read in conjunction with the appended drawings,in which:

FIG. 1 is a top view, partly in section, of a preferred embodiment of aninstrument built in accordance with the present invention;

FIG. 2 is a side view of the same instrument;

FIG. 3 is a sectional view of the same instrument, taken along the lines3-3 in FIG. 2; and

FIG. 4 is a bottom view of the same instrument, showing particularly thecutting edge, blade guards and rollers.

In FIGS. 1 and 2, there may be seen a frame 12 which includes an uppercross-member 14 and upright members 16 and 18 The upright members areconnected at their upper surfaces in fixed spaced relationship by theupper cross-member 14, into which screws 20 and 22 are threaded. Theuprights are also connected together and spaced by means of a lowercross-member 24, which is firmly attached to the upright 16 by means ofscrews 26 and 28 and to the upright 18 by means of screws 30 and 32. Thevarious frame members could, of course, be held in proper spacedrelationship by other suitable connecting elements or, alternatively,the entire frame could be cast as a single piece.

Mounted upon the upper cross-member 14 is a handle 34, by meansexplained in greater detail below and shown in another view. The handleis preferably knurled or fluted in order that the instrument may be heldby the operator Without risk of slipping or other untoward movement.Adjacent the top of the handle 34 are various calibrated markings whichserve in conjunction with a rotatable cap 36 to form a micrometer head.The cap 36 is also preferably knurled or fluted, and marked on the capis a vertical line or arrow to show the rotary position of the caprelative to the handle 34.

Extending downwardly from the cap and through the handle 34 and thecross-member 14 is a shaft 38, a portion of the lower end of which isthreaded. The threaded end of the shaft is screwed into a guard mount40. The mount 40 is disposed for sliding movement in slots 42 and 44formed in the inner sides of the frame uprights 16 and 18, respectively.A pair of springs 46 and 48 are compressed between the guard mount 40and the upper cross-member 14. Suitable openings are formed in both theunderside of the cross-member 14 and the top surface of the guard mount40 to maintain the springs 46 and 48 in position. Movement of the cap 36relative to the handle 34 causes the guard mount 40 to be advanced orretracted in its slots against the loading provided by the springs 46and 48, the amount of such movement being indicated by the calibrationson the handle 34.

At the forward or left-hand end of the uprights, as they are seen inFIGS. 1 and 2, are downwardly extending legs which are drilled to formopenings for receiving nylon or Teflon bushings and a shaft 59 Mountedon the shaft 50 is a grooved roller 52. The shaft 50' and the roller 52may be turned from a single piece or the rollers may be mounted uponstub shafts serving as pivots to permit free motion of the roller 52.Similar extensions, openings and bushings are provided at the back orrighthand end of the uprights to accommodate a roller 54.

The uprights 16 and 18 also include upwardly extending portions 56 and58. countersunk openings are formed in the two upward extensions, andbushings preferably made ofTeflon, nylon or other suitable material arepressed in the openings. The bushing 60 shown in the section of theupward extension 56 is identical to that utilized in the upwardextension 58.

Mounted for reciprocal movement in the bushing 60 and its counterpart inthe upright 58 is a shaft 62. One end of the shaft 62 is turned througha 90 angle to form a handle 64. A yoke 66 is attached to the shaft 62 bymeans of collars 68 and 70 and set screws 74 and 76 which are threadedinto the collars to bear against the shaft 62. Mounted on the upwardextensions 56 and 58 is a guide plate 78 which extends downwardly andforwardly into the center of the frame for purposes explained in detailbelow. The yoke 66 extends beneath the guide plate and supports a fixedblade-holding element 80. The fixed element may, in fact, be integralwith the yoke 66. A movable blade-holding element 82 is pivoted from apair of lugs 84 and 86 and cooperates with the fixed holder 80 to hold ablade 88 sandwiched between the blade-holding members. A pair of springs90 and 92 are attached between pins on the yoke 66 and pins on themovable blade-holding member to insure toggle action in order that theblade-holding elements may be held in either a fixed open position or afixed closed position.

In addition to the toggle, a positive lock is provided to preventmovement or slipping of the blade 88 between the blade-holding members80 and 82. It consists of a lever 94 which pivots upon a pin 96 set inthe yoke 66. The outer end of the lever 94 extends beneath the shaft 62outwardly to a position where it may be easily manipulated. The innerend of the lever 94 projects beneath an extension 98 formed adjacent oneof the pivots of the movable blade-holding element 82. With the innerend of the lever 94 between the yoke and the blade holder extension 98,the movable blade-holding element may not be rotated. Extendingdownwardly from the yoke is a guidepost 100, at the lower extremity ofwhich two bearing buttons of Teflon, nylon or other suitable materialare provided, the button 106 being typical. The central area of theroller 54 is not grooved, and the buttons bear against the smoothsurface of the roller to aid in maintaining alignment of the blade andits supporting mechanism relative to the frame 12.

Adjustment of the depth of cut is provided by the previously mentionedcap 36 and handle 34 which form a micrometer head. In FIG. 3, details ofone method of attachment of the handle 34 to the upper cross-member 14are shown. In this instance, a pair of screws 110 and 112 are used, butthe handle could be threaded into the crossmember or other suitablemechanical means could be used. Also, in FIG. 3, the retaining openingsfor the springs 46 and'48 in the upper cross-member 14 and the guardmount 40 are clearly visible. The lower edge of the front of the guardmount plate 40 is relieved to form a shoulder 102, and a vertical slot104 is formed in that shoulder to accommodate a pair of slideabletransverse blade guards or masks 114 and 116. The guards are retained inthe vertical slot of the guard mount 40 by means of screws 118 and 120.The screws 118 and 120 pass through horizontal slots in the guards 114and 116 and are threaded into the relieved portion of the mounting plate40. In addition to the vertical solt formed in the lower edge of themounting plate 40, a horizontal slot 122 is also formed in the front ofthe relieved portion of the plate. The guards 114 and 116 are providedwith key tongues 124 and 126 which closely fit into the slot 122 andserve as guides for the guards when they are moved.

In FIG. 4, the underside of the instrument is shown in some detail. Thearrangement of the movable blade-holding member and the locking of thatmember by the lever 94 may be seen quite clearly. The lever 94 pivotsupon the pin 96 which is set in the yoke 66. Beyond the pin 96, theoperative extension of the lever 94 may be seen to project beneath theextension 98 of the movable blade-holding element 8-2, preventingaccidental rotation of the element from its closed position. Also, thebearing buttons and their relationship to the smooth central portion ofthe roller 54 may be seen. The bearing buttons serve to assuremaintenance of alignment betwene the movable yoke and the roller 54which is, of course, fixed in position relative to the frame 12.

The action of the guards or masks 114 and 116 may easily be understoodby reference to FIGS. 3 and 4. As is obvious, the close fit of theguards 114 and 116 themselves in the vertical slot 104 and the similarclose fit of the key tongues 124 and 126 in the horizontal slot 122serves to prevent undesired movement of the masks in either of twoplanes after they are set by. the locking screws 118 and 120. Rotationof the cap 36 causes the guards 114 and 116 to be raised or lowered,varying the vertical exposure of the blade 88 in the area between themasks.

Blade replacement is effected by moving the lever 94 to the unlockedposition and snapping the movable bladeholding element to its openposition. Two or more pins, such as the pins 89 and 91, extend from thesurface of the blade-holding element 82, and openings are formed in thesurface of the other element to accommodate the pins. Correspondingopenings are provided in the blade 88, and it is thus held in fixedposition when the blade-holding members are snapped together and lockedby movement of the lever 94.

In operating the device, the surgeon first sets the guards 114 and 116to obtain a desired width of out. He then adjusts the cap 36 relative tothe handle 34 to lift the marks 114 and 116 to a point at which theproper blade exposure for the desired depth of cut is obtained. FIG. 2illustrates the actual operation of the instrument after the desiredsettings are made. The instrument is held by the handle 34 against theskin from which a segment is to be taken. With a light amount ofpressure on the instrument, the skin is brought up behind the roller 52as a uniform mound of tissue. The instrument is moved over the skinsurface steadily and easily. The front or mounding roll 52 and the rearroll 54 are in fixed position so that the elevated mound of tissue atthe edge of the blade is always uniform and under the same tension.Accordingly, the skin being cut away is completely uniform regardless ofthe consistency of the underlying soft tissue. The handle 64 isreciprocated by the other hand of the surgeon in a simple to-and-fromotion to slice a uniform segment of skin. To avoid any variable factorsin operating the device, it is desirable that the blade 88, which asnoted is replaceable, should be a new blade in each operating procedure.The skin se mentbeing removed rides up over the fixed blade-holdingelement and'over the depending edge of the guide plate 78, from which itmay easily be removed.

Although what has been described constitutes a preferred embodiment ofthe invention, various modifications and changes will occur to thoseskilled in the art upon a reading of the foregoing specification. Forexample, the vertical blade exposure adjustment need not be incorporatedWithin the handle, nor must the handles be formed exactly as shown.Other operators might prefer independent adjustment or differentconfigurations of handles or levers. Similarly, the horizontaladjustment of the blade guard might well be changed so that a singlemember or a portion of such a member might be moved to obtain desiredwidth of blade exposure. These and similar modifications or variationsof design are believed to be within the preview of the present inventionwhich should be limited only by the spirit and scope of the appendedclaims.

What is claimed is:

1. In a dermatome for taking segments from the skin surface, saiddermatome including a frame and a pair of rollers mounted in parallelspaced relationship for rotation in and beneath said frame, thecombination of a cutting blade disposed in said frame between andparallel to said rollers, means for applying said rollers to said skinsurface, a hollow handle attached to said frame whereby said frame maybe manually moved over said skin surface with said rollers maintained incontact therewith to cause said skin to rise in a uniform mound betweensaid rollers in close apposition to said blade, a guard masking thecutting edge of said blade, means within said hollow handle attached tosaid guard for adjusting the amount of vertical exposure of said bladein accordance with the position of said guard relative to said blade,and means for manually reciprocating said blade in said frame along aline parallel to said rollers during movement of said rollers over saidskin surface to cut a segment therefrom.

2. In a dermatome for taking segments from the skin surface, saiddermatome including a frame and a pair of rollers mounted in parallelspaced relationship for rotation in and beneath said frame, thecombination of a hollow handle attached to said frame, a cap disposedupon said handle and rotatable relative thereto, a cutting bladedisposed in said frame between and parallel to said rollers, a guardadjacent to and aligned with said blade, a threaded shaft connectingsaid guard to said cap whereby rotation of said cap varies the verticalexposure of said blade to vary the depth of cut of segments from saidskin surface.

3. In a dermatome as defined in claim 2, the further combinationtherewith of cooperating calibration markings on said handle and saidcap, said calibrations being related to the vertical position of saidguard relative to said blade, whereby a micrometer head is formed.

4. In a dermatome for taking segments from the skin surface, saiddermatome including a frame and a pair of rollers mounted in parallelspaced relationship for rotation in and beneath said frame, thecombination of a yoke disposed for reciprocal movement in said frameparallel to said rollers, a fixed blade-holding element carried by saidyoke, a movable blade-holding element pivotably mounted on said yoke,toggle apparatus connecting said yoke and said movable blade-holdingelement whereby said movable blade-holding element is releasably urgedinto a first position closely adjacent said fixed blade-holding element,a cutting blade retained between said blade-holding elements when saidmovable blade-holding element is closely adjacent said fixedblade-holding element, said toggle apparatus releasably holding saidmovable blade-holding element in a second position remote from saidfixed blade-holding element upon actuation thereof for removal of saidblade.

5. In a dermatome as defined in claim 4, the further combinationtherewith of pins disposed in one of said blade-holding elements, theother of said blade-holding elements having openings formed therein forreceiving said pins, said blade having similar openings formed thereinfor passage therethrough of said pins to hold said blade in a fixedpredetermined position in said bladeholding elements.

6. In a dermatome as defined in claim 4, the further combinationtherewith of an extension formed on said movable blade-holding elementand disposed within said frame and a lever pivotably mounted on saidyoke, a projection of said lever being rotatable into a position beneathsaid extension to lock said movable blade-holding element in said firstposition.

7. A dermatome for taking segments from the skin comprising a frame, apair of rollers mounted in spaced parallel relationship for rotation inand beneath said frame, an upper cross-member forming a portion of saidframe, a first handle attached to said crossamember, a yoke mounted forreciprocation in said frame along a line parallel to said rollers, afixed blade-holding element carcried by said yoke between said rollers,a cutting blade mounted against said fixed blade-holding element, amovable blade-holding element pivoted from said yoke, a toggle forurging said blade-holding elements together in a first position forholding said blade therebetween, and a second handle attached to saidyoke, whereby said dermatome may be held by said first handle with saidrollers against said skin to bring said skin into close apposition tosaid cutting blade, and said second may be reciprocated to cut a segmentfrom said skin surface as said dermatome is moved over said skinsurface.

8. A dermatome for taking segments from a skin surface comprising aframe, a pair of rollers mounted for rotation in and beneath said framewith their axes in spaced parallel relationship, a cutting blade mountedfor reciprocation along a line parallel to and between said rollers tocut segments from said skin surface as said rollers pass thereover, ablade guard adjacent said blade, a micrometer head mounted on said frameand connected to said blade guard to vary the exposure of said blade ina direction normal to the plane of the axes of said rollers, and meansfor adjusting the position of at least a portion of said guard along aline parallel to said axes to adjust the amount of exposure of saidblade along said line.

References Cited UNITED STATES PATENTS 1,594,613 8/1926 Hagen 1283051,935,605 5/ 1932 Altruda 128305 2,457,772 12/1948 Brown et al. 128305RICHARD A. GAUDET, Primary Examiner. G. E. MCNEILL, Assistant Examiner.

1. IN A DERMATOME FOR TAKING SEGMENTS FROM THE SKIN SURFACE, SAIDDERMATOME INCLUDING A FRAME AND A PAIR OF ROLLERS MOUNTED IN PARALLELSPACED RELATIONSHIP FOR ROTATION IN AND BENEATH SAID FRAME, THECOMBINATION OF A CUTTING BLADE DISPOSED IN SAID FRAME BETWEEN ANDPARALLEL TO SAID ROLLERS, MEANS FOR APPLYING SAID ROLLERS TO SAID SKINSURFACE, A HOLLOW HANDLE ATTACHED TO SAID FRAME WHEREBY SAID FRAME MAYBE MANUALLY MOVED OVER SAID SKIN SURFACE WITH SAID ROLLERS MAINTAINED INCONTACT THEREWITH TO CAUSE SAID SKIN TO RISE IN A UNIFORM MOUND BETWEENSAID ROLLERS IN CLOSE APPOSITION TO SAID BLADE, A GUARD MASKING THECUTTING EDGE OF SAID BLADE, MEANS WITHIN SAID HOLLOW HANDLE ATTACHED TOSAID GUARD FOR ADJUSTING THE AMOUNT OF VERTICAL EXPOSURE OF SAID BLADEIN ACCORDANCE WITH THE POSITION OF SAID GUARD RELA-